The Average Exposure Indicator expressed in μg/m3 (AEI) shall be based upon measurements in urban background locations in zones and agglomerations throughout the territory of a Member State. It should be assessed as a three-calendar year running annual mean concentration averaged over all sampling points established pursuant to Section B of Annex V. The AEI for the reference year 2010 shall be the mean concentration of the years 2008, 2009 and 2010.
However, where data are not available for 2008, Member States may use the mean concentration of the years 2009 and 2010 or the mean concentration of the years 2009, 2010 and 2011. Member States making use of these possibilities shall communicate their decisions to the Commission by 11 September 2008.
The AEI for the year 2020 shall be the three-year running mean concentration averaged over all those sampling points for the years 2018, 2019 and 2020. The AEI is used for the examination whether the national exposure reduction target is met.
The AEI for the year 2015 shall be the three-year running mean concentration averaged over all those sampling points for the years 2013, 2014 and 2015. The AEI is used for the examination whether the exposure concentration obligation is met.
| Exposure reduction target relative to the AEI in 2010 | Year by which the exposure reduction target should be met | |
|---|---|---|
| Initial concentration in μg/m3 | Reduction target in percent | 2020 |
| < 8,5 = 8,5 | 0 % | |
| > 8,5 — < 13 | 10 % | |
| = 13 — < 18 | 15 % | |
| = 18 — < 22 | 20 % | |
| ≥ 22 | All appropriate measures to achieve 18 μg/m3 | |
Where the AEI in the reference year is 8,5 μg/m3 or less the exposure reduction target shall be zero. The reduction target shall be zero also in cases where the AEI reaches the level of 8,5 μg/m3 at any point of time during the period from 2010 to 2020 and is maintained at or below that level.
| Exposure concentration obligation | Year by which the obligation value is to be met |
|---|---|
| 20 μg/m3 | 2015 |
| Averaging period | Target value | Date by which target value should be met |
|---|---|---|
| Calendar year | 25 μg/m3 | 1 January 2010 |
| a Stage 2 — indicative limit value to be reviewed by the Commission in 2013 in the light of further information on health and environmental effects, technical feasibility and experience of the target value in Member States. | |||
| Averaging period | Limit value | Margin of tolerance | Date by which limit value is to be met |
|---|---|---|---|
| STAGE 1 | |||
| Calendar year | 25 μg/m3 | 20 % on 11 June 2008, decreasing on the next 1 January and every 12 months thereafter by equal annual percentages to reach 0 % by 1 January 2015 | 1 January 2015 |
| STAGE 2a | |||
| Calendar year | 20 μg/m3 | 1 January 2020 | |